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Free radical generation plays a key role in killing bacteria by antibiotics. However, radicals are short-lived and reactive, and thus difficult to detect for the state of the art. Here we use a technique which allows optical nanoscale magnetic resonance imaging (MRI) to detect radical generation on the scale of single bacteria. We demonstrate that the radical generation in Staphylococcus aureus increases in the presence of UV irradiation as well as vancomycin and is dependent on the antibiotic's dose. With a method based on ensembles of nitrogen vacancy (NV) centers in diamond, we were able to follow the radical formation near individual bacteria over the whole duration of the experiment to reveal the dynamics of radical generation. Using this new approach, we observed free radical concentrations within nanoscale voxels around the diamond particles and determined its exact timing depending on the antibiotic dose. Since changes in the response to antibiotics emerge in only a few bacteria of the entire population, such a single-cell approach can prove highly valuable for research into drug resistance.

The first synthesis of 2,4-bis(3,4-dimethoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-disulfide (SAV-A1 reagent) was achieved. Seven oxo-alkyl esters (HLn) were synthesized thereof. Ni(II) complexes ([Ni(Ln)(2)]) of these ligands were prepared in ethanol. The structures were identified by spectral studies. Ni(II) complexes were unambiguously determined by X-ray crystallography. In addition, the ligands and their Ni(II) complexes were tested on two different human cancer cell lines, including liver and colon. Moreover, density functional theory (DFT) calculations of the Ni(II) complexes were performed, and the molecular docking studies of these compounds with liver cancer protein, PDB ID: 3WZE and colon cancer antigen proteins, ID 2HQ6 were presented to investigate and predict potential interactions.

Nucleophilic ionic sources of fluoride are essential reagents in the synthetic toolbox to access high added-value fluorinated building blocks unattainable by other means. In this review, we provide a concise description and rationale of the outstanding features of one of these reagents, tetramethylammonium fluoride (TMAF), as well as disclosing the different methods for its preparation, and how its physicochemical properties and solvation effects in different solvents are intimately associated with its reactivity. Furthermore, herein we also comprehensively describe its historic and recent utilization, up to December 2021, in C-F bond-forming reactions with special emphasis on nucleophilic aromatic substitution fluorinations with a potential sustainable application in industrial settings, as well as its use as a base capable of rendering unprecedented transformations. Keywords: tetramethylammonium fluoride; TMAF; solvation effects; nucleophilic fluorination; sustainable industrial fluorination; SNAr; [18F]-radiolabelling; superbases; selective methylation; fluorinated excited species

Free radicals play a key role in the ageing process. However, free radicals are small, reactive and short lived and thus challenging to measure. We utilize a new technique called diamond magnetometry for this pur-pose. We make use of nitrogen vacancy centers in nanodiamonds. Via a quantum effect these defects convert a magnetic resonance signal into an optical signal. While this method is increasingly popular for its unprecedented sensitivity in physics, we use this technique here for the first time to measure free radicals in living cells. Our signals are equivalent to T1 signals in conventional MRI but from nanoscale voxels from single cells with sub-cellular resolution. With this powerful tool we are able to follow free radical gen-eration after chemically inducing stress. In addition, we can observe free radical reduction in presence of an antioxidant. We were able to clearly differentiate between mutant strains with altered metabolism. Finally, the excellent stability of our diamond particles allowed us to follow the ageing process and differentiate between young and old cells. We could confirm the expected increase of free radical load in old wild type and sod1 Delta mutants. We further applied this new technique to investigate tor1 Delta and pex19 Delta cells. For these mutants an increased lifespan has been reported but the exact mechanism is unclear. We find a decreased free radical load in, which might offer an explanation for the increased lifespan in these cells.(c) 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).

Poly(aminoethyl methacrylate) (PAEMA), poly-(ethylene oxide)-block-(aminoethyl methacrylate) (PEO-PAEMA), and their guanidinylated derivates, poly(guanidine ethyl methacry-late) (PGEMA) and poly(ethylene oxide)-block-(guanidine ethyl methacrylate) (PEO-PGEMA), were prepared to study their capabilities for CO2 adsorption and release. The polymers of different forms or degree of guanidinylation were thoroughly characterized, and their interaction with CO2 was studied by NMR and calorimetry. The extent and kinetics of adsorption and desorption of N-2 and CO2 were investigated by thermogravimetry under controlled gas atmospheres. The materials did not adsorb N-2, whereas CO2 could be reversibly adsorbed at room temperature and released by an elevated temperature. The most promising polymer was PGEMA with a guanidinylation degree of 7% showing a CO2 adsorption capacity of 2.4 mmol/g at room temperature and a desorption temperature of 72 degrees C. The study also revealed relations between the polymer chemical composition and CO2 adsorption and release characteristics that are useful in future formulations for CO2 adsorbent polymer materials.